Digital discs are pervasive in computer operations. They may take various configurations but DVD (digital video discs) and CD-ROM (compact discs-read only memory) are two of the more common. The construction of the discs comprises, typically, a layer of aluminum on which is deposited the digital data to be read and a plastic coating which overlays the data on the aluminum disc and provides some measure of protection for the data.
Digital discs may be and are frequently damaged. This is particularly the case where the discs are temporarily used such as in rental operations and the like where customers of such rental operations have no particular reason to take care of such discs during rental. This results in the discs being returned to the rental establishment in a damaged condition.
Compact discs are expensive to replace and since the data underlying the plastic overlay typically still retains its integrity, there is reason to restore the disc to its original condition or, at least, to a condition where the data can be properly read through the plastic layer. By so doing, the need for discarding the damaged disc and purchasing a further disc is obviated and money is saved.
Reconditioning the protective overlay coating in a digital disc is known. Such an apparatus and method is described and illustrated, for example, in U.S. Pat. Nos. 5,954,566 and 5,733,179, both to Bauer. These patents teach a technique for reconditioning a protective coating by using a buffing tool which buffs the damaged protective coating on the disc. The disc is mounted on a turntable which has a controllable rotation speed. The buffing tool is brought into contact with the protective coating and rotated by a motor. By rotating the buffing tool, the protective coating is reconditioned to allow optical reading of the data. However, manual manipulation of the disc is required before, during and after the buffing operation.
Canadian Patent 2,230,394 (Perego) teaches an automatic technique for producing optical discs. Work stations are located in two parallel advance lines. The disc being produced advances down one line and returns on the other line. However, there is no teaching of reconditioning digital discs.
Canadian patent application serial no. 2,169,609 teaches a method and apparatus for reconditioning compact discs. The technique, however, similar to the Bauer teachings, uses manual operation to refurbish the damaged coating of compact discs. The manual operation clearly puts limits on the number of discs that may be damaged and reconditioned and the efficiency of reconditioning large numbers of digital discs.